Trioxorhenium(VII) alkoxides, di-isopropylamides, carboxylates and related compounds

A number of trioxorhenium(VII) compounds of the type ReO3X (X = NPri2, OMe, OBut, or O2CR; R = Me, CF3, But, or Ph) have been prepared from ReO3Cl, ReO3(OSiMe3), and Re2O7. The compounds form adducts with tetrahydrofuran, pyridine (py), 2-hydroxypyridine, and NNN′N′-tetramethylethylenediamine (tmen); examples are ReO3(OMe)(tmen) and ReO3(O2CMe)(py). For the carboxylates, the RCO2 group may be unidentate or chelate depending upon the nature of the additional ligand. The acetatotrioxocomplex undergoes an exchange reaction with benzoic acid to give the corresponding benzoate. A five-co-ordinate rhenium(VII) complex with trimethylsilyl-amide, -imide, and -oxide groups, Re[N(SiMe3)2](NSiMe3)2(OSiMe3)2, is also described, I.r. and n.m.r. (1H, 13C) data are given.